Tires Turf tires for my Yanmar

[Ductape]

20x8x10 has a rolling circumference of 58

 

[Whiskey]

Ductape:

I ain't no mathematician (hope you spelled that right, I copied you) but,

<font color="red">My 186D came with a 9.5x16 rear, and 6x12 front..... different than your manual which puts the 9.5x16 with a 5x12 </font>

I think it's the last number that you need to worry about. Be it 6x12 or 5x12, there both 12 and thats the height. Width is not part of the math.....just height.

Some one who has a better grip on this chim in so I don't give him bad info!!!!!

 

[Whiskey]

Ductape:

<font color="red">A 9.5x16 tire has a rolling circumference of 98"
A 31x15.5x15 is 89"
A 6x12 is 69"
So who is a mathematician and can tell me what size turf tire i need to go along with my 31x15.5x15??
</font>

Me thinks you got this wrong....our I'm reading you question and not understanding it right.

AG, turf or R4's it does not matter....just keep the same size listed from the manual. In other words don't cross a rear AG tire with a turf size tire.....if you want truf you can pic any group of tires sizes listed for any of the options I showed but stay with that grouping front and rear.

From what I listed....you got the right size front to rear with the turf's you bought....

Thanks for the words on the tractor.....took me forever to get it painted but was a fun project and I'm very happy with the out come

 

[FL_Jerry]

The ratio you set up.. 98/89 to 69/x is 62.66 You can figure this by cross multiplying the top and bottom numbers. 98*X=69*89. To get the value of X, divide by 98.

When I first looked at this I thought the rolling length= the Circumference of a circle,(Diameter * Pi(3.14159)). The tires listed do not match this, well the treads don't at least. Tires have give to them at a selected inflation pressure, changing the actual Diameter. I think the manufacturers numbers reflect this.

Jerry

 

[Normmm]

Hey Guys

I am not finding the rolling curcumference info. Please attach a link to some of this rc data. I am very insteested in 6.00x14 and 9.5x24 rc.

Norm_ala

 

[Ductape]

Whiskey,
I think we are on the same page. Since my tires match what is in the manual, (assuming the 186D and 187D have no difference in gearing) then the tires i bought SHOULD work just fine. I was assuming there would be a slight diameter difference between the 5x12 and 6x12.... but perhaps i was mistaken. I guess what i'm hoping for, is for someone who is more intimate with these tractors than i to teel me the tractors are virtually the same, and shared the same gear ratios...... and that there were no gear ratio differences between the ag and turf tire options. Its been so wet here this week i have not even had a chance to get it out and try the tractor in four wheel drive. I'm probably making more to worry about than i need to, but i don't want expensive surprises due to driveline binding in 4wd.

Jerry,
Thanks.... my math is a bit rusty, as it has been a couple *ahem* years since i was in school. I couldn't remember the formula, but i knew someone here would be able to help me !

Norm,
Check out www.FirestoneAg.com Its plenty informative... at least as far as Firestone and Bridgestone tires are concerned. They list rim widths, overall diameters and such. Hopefully it will prove you with the info you are looking for.

Can anyone else confirm what Whiskey and i think..... that the 186D and 187D shared the same drivelines ?? /forums/images/graemlins/confused.gif

Scott

 

[pennwalk]

Ductape,

I think the stock turfs for the 186/186D were 31-10.50-15 and 23.5-8.00-10. I believe that the rims were 10X15 and 6X10.

Chris

 

[Ductape]

Well, it finally dried up enough to take the tractor out last weekend. I tried driving with the front axle engaged over soft dirt, and the front tires left tracks... indicating to me that the overall gearing with my front turfs is off a bit. It did go into, and out of four wheel drive without any problems though. I suspect i will have to come up with a front tire that is a bit taller.

 

[Ductape]

I must add how much more stable it feels with the wider footprint. Its nearly 60 inches wide in the rear now! Its taking a little getting used to..... having to pay a bit more attention when driving around obstacles. I need to get my belly mower cleaned up now that i can drive on the lawn without digging it up.

Chris.... thanks for the 186D tire info. I assumed wrong. The 186 and 187 must not have shared the same gear ratio ! Whoda thought ??!!

 

[Normmm]

Could you tell if the front tires were sliding or were they pulling. Most 4wd's have a little overrun front to rear so the fronts whould be pulling the rears a little. But if they are sliding that will not do you will not be able to control the tractor at speed.